Light-emitting diode and manufacturing method thereof

ABSTRACT

A light-emitting diode (LED) and manufacturing method thereof are disclosed. The LED includes a transparent substrate, a plurality of transparent conductive layers, a plurality of metal circuits, and a LED chip. The LED chip is suitable for emitting a light and a portion of the light emits toward the transparent substrate. The manufacturing method of LED includes the following steps. First, a transparent conductive layer is formed on the transparent substrate. Next, a conductive pattern is fromed by etching transparent conductive layer. The intersection metal circuit is formed by disposing the metal on a portion of the transparent conductive layer. Finally, the LED chip is disposed on the metal circuit so tat the LED chip is electrically connected to the metal circuit.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority benefit of Taiwan application serial no. 98140165, filed on Nov. 25, 2009. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of specification.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a light emitting diode (LED) and a manufacturing method thereof More particularly, the present invention relates to a light emitting diode with double-side emission and a manufacturing method thereof

2. Description of Related Art

Due to advantages of low power consumption and small volume, LEDs have been extensively applied to fabrication of different sized array light emitting module and applied in indicators in information, communication and consumptive electronic appliances and display devices.

The light emitting module with double-side emission can be applied in the electronic devices, such as LED advertisement display screens or flip-open type cell phones. The light emitting module with double-side emission may achieve the goal of reducing the manufacturing costs, weight and thickness by using a panel with double-side emission.

No matter the conventional packaging process of the LED module using the single LED package, the surface-mount device or the flip-chip package, the finished products requires soldering on the printed circuit board to connect the electronic circuit structure in the final steps. However, the light emitting chip is fixed on the non-transparent printed circuit board, and the goal of the double-side emission can not be accomplished.

In addition, a light emitting module can have a plurality of LED dies with different color, simultaneously. Taking the white LED module of the backlight module as an example, because the white LED module is made with red, green and blue LEDs, the epitaxial materials of different color die are difference, and further the voltage characteristics are difference and the design of the control circuit is more complex.

Therefore, since the light emitting module requires a complex circuit design to satisfy the demand, the LED module and packaging method thereof can be achieved the goal of double-side emission.

SUMMARY OF THE INVENTION

The present invention provides a light-emitting diode with double-side emission and a manufacturing method thereof.

According to one embodiment of the present invention, a light-emitting diode (LED) is provided. The LED includes a transparent substrate, a first transparent conductive layer, a second transparent conductive layer, a plurality of metal circuits and a LED chip.

The first transparent conductive layer and the second transparent conductive layer are respectively disposed on a region of the transparent substrate and electrically isolated from each other. The metal circuits are disposed on the first transparent conductive layer and the second transparent conductive layer respectively, and cover the portions of the first transparent conductive layer and the second transparent conductive layer. The LED chip is disposed on the metal circuits and electrically connected to the metal circuits. The LED chip is suitable for emitting a light, and a portion of the light emits toward the transparent substrate.

According to one embodiment of the present invention, the manufacturing method of LED includes forming a first transparent conductive layer and a second transparent conductive layer by plating a transparent conductive material on the transparent substrate and etching the transparent conductive material. A plurality of metal circuits is respectively disposed on portions of the first transparent conductive layer and second transparent conductive layer. The LED chip is disposed on the metal circuits so that the LED chip is electrically connected to the metal circuits.

According to another embodiment of the present invention, a LED is provided. The LED includes a transparent substrate, a transparent conductive pattern layer, a first metal circuit, a second metal circuit, an insulating layer and a LED chip. The transparent conductive pattern layer is disposed on the transparent substrate, and the first metal circuit and the second metal circuit on the transparent conductive pattern layer intersect with each other. The insulating layer is disposed between the second metal circuit and the first metal circuit to electrically isolate the first metal circuit and the second metal circuit. The LED chip is disposed on the first metal circuit and the second metal circuit and electrically connected to the first metal circuit and the second metal circuit. The LED chip is suitable for emitting a light, and a portion of the light emits toward the transparent substrate.

According to one embodiment of the present invention, the manufacturing method of LED includes forming a transparent conductive pattern by plating a transparent conductive material on the transparent substrate and etching the transparent conductive material. The first metal circuit is deposited on a portion of the transparent conductive pattern, and the second metal circuit is deposited on the other portion of the transparent conductive pattern, so that the first metal circuit and the second metal circuit on the transparent conductive pattern layer intersect with each other, and the first metal circuit and the second metal circuit are isolated form each other through the insulating layer disposed between the first metal circuit and the second metal circuit. The LED chip is disposed on the first metal circuit and the second metal circuit and electrically connected to the first metal circuit and the second metal circuit.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to make the above and other objects, features and advantages of the present invention more comprehensible, several embodiments accompanied with figures are described in detail below.

FIG. 1 A is a schematic cross-sectional diagram showing a transparent conductive material layer formed on a transparent substrate according to one embodiment of the present invention.

FIG. 1B is a schematic cross-sectional diagram showing a first transparent conductive layer and a second transparent conductive layer formed on the transparent conductive material layer depicted in FIG. 1A.

FIG. 1C is a schematic cross-sectional diagram showing the metal circuits deposited on the first transparent conductive layer and the second transparent conductive layer depicted in FIG. 1B.

FIG. 1D is a schematic cross-sectional view of an LED chip disposed on the metal circuits depicted in FIG. 1C.

FIG. 2 is a top view schematically illustrating the LED chip depicted in FIG. 1D.

FIG. 3A is a schematic cross-sectional diagram showing a transparent conductive material layer formed on a transparent substrate according to another embodiment of the present invention.

FIG. 3B is a schematic cross-sectional diagram showing a transparent conductive pattern formed on the transparent conductive material layer depicted in FIG. 3A.

FIG. 3C is a schematic cross-sectional diagram showing the metal circuits deposited on the transparent conductive pattern depicted in FIG. 3B.

FIG. 3D is a schematic cross-sectional view of an insulating layer formed on the first metal circuit and the second metal circuit depicted in FIG. 3C.

FIG. 3E is a schematic cross-sectional view of a metal layer formed on the insulating layer depicted in FIG. 3D to connect the different sections of the second metal circuit.

FIG. 3F is a schematic cross-sectional view of an LED chip disposed on the first metal circuit and the second metal circuit depicted in FIG. 3E.

FIG. 4 is schematic views showing an intersection circuit according to the manufacturing flow charts depicted in FIG. 3A-3F.

DESCRIPTION OF EMBODIMENTS

FIGS. 1A-1D are schematic cross-sectional flowcharts illustrating a manufacturing process of a light-emitting (LED) diode according to an embodiment of the present invention.

First, as shown in FIG. 1A, a transparent substrate 100 whereon a transparent conductive material layer 110 has been formed is provided. A method of forming the transparent conductive material layer 110 is, for example, evaporation. A thickness of the transparent conductive material layer 110 can be between 1600˜2100 angstrom (Å), and a resistance of the transparent conductive material layer 110 is 10 ohmic (Ω).

FIG. 1B is a schematic cross-sectional diagram showing a first transparent conductive layer and a second transparent conductive layer formed on the transparent conductive material layer depicted in FIG. 1A. The first transparent conductive layer 113 and the second transparent conductive layer 114 are formed through etching the transparent conductive material layer 110. The method for etching the transparent conductive material layer 110 is, for example, a lithography and etching process.

FIG. 1C is a schematic cross-sectional diagram showing the metal circuits deposited on the first transparent conductive layer and the second transparent conductive layer depicted in FIG. 1B. The metal circuit 133 is deposited on a portion of the first transparent conductive layer 113, and the metal circuit 134 is deposited on a portion of the second transparent conductive layer 114.

FIG. 1D is a schematic cross-sectional view of an LED chip disposed on the metal circuits depicted in FIG. 1C. The LED chip 140 is disposed on the first metal circuit 133 and the second metal circuit 134, so that the LED chip 140 is electrically connected to the first metal circuit 133 and the second metal circuit 134. The LED chip 140 is disposed on the metal circuit by flip chip, and the method of disposing includes fixing the LED chip 140 on the metal circuit through a silver glue of a eutectic bonding.

FIG. 2 is a top view schematically illustrating the LED chip depicted in FIG. 1D. The cross-sectional structure along line 1D in FIG. 2 is as shown in the FIG. 1D. The LED 150 includes a transparent substrate 100, a first transparent conductive layer 113, a second transparent conductive layer 114, a first metal circuit 133, a second metal circuit 134 and a LED chip 140.

The first transparent conductive layer 113 and the second transparent conductive layer 114 are respectively disposed on a region of the transparent substrate 100 and electrically isolated from each other. The first metal circuit 133 is disposed on the first transparent conductive layer 113 and covers a portion of the first transparent conductive layer 113. The second metal circuit 134 is disposed on the second transparent conductive layer 114 and covers a portion of the second transparent conductive layer 114. The LED chip 140 is disposed on the first metal circuit 133 and the second metal circuit 134 and electrically connected to the first metal circuit 133 and the second metal circuit 134. The LED chip 140 is suitable for emitting a light, and a portion of the light emits toward the transparent substrate.

According to an embodiment of the present invention, the substrate comprises a glass substrate, a plastic substrate or a flexible substrate. The thickness of the transparent substrate can be 1.1 micrometers (μm). The transparent conductive layer can be a conductive layer with indium tin oxide. The material of the metal circuit is, for example, gold, aluminum, copper, or alloy thereof.

FIGS. 3A-3F are schematic cross-sectional flowcharts illustrating a manufacturing process of a light-emitting diode (LED) according to another embodiment of the present invention.

FIG. 3A is a schematic cross-sectional diagram showing a transparent conductive material layer formed on a transparent substrate. A transparent conductive material 210 is plated on a transparent substrate 200. A method of forming the transparent conductive material 210 is, for example, evaporation. A thickness of the transparent conductive material 210 can be between 1600˜2100 angstrom (Å), and a resistance of the transparent conductive material layer 210 is 10 ohmic(Ω).

FIG. 3B is a schematic cross-sectional diagram showing a transparent conductive pattern formed by etching the transparent conductive material layer 210. Patterns 212 a, 212 b, 212 c are formed by etching the transparent conductive material layer 210. The method for etching the transparent conductive material layer 210 is, for example, a lithography and etching process.

FIG. 3C is a schematic view of the metal circuits deposited on the transparent conductive pattern 212. The first metal circuit 222 is deposited on a portion of the pattern 212 c of the transparent conductive pattern, the section 223 a of the second metal circuit 223 is deposited on a portion of the pattern 212 a, and the section 223 b of the second metal circuit is deposited on a portion of the pattern 212 b.

FIG. 3D is a schematic view of an insulating layer formed on the first metal circuit 222. The insulating layer 230 covers a portion of the first metal circuit 222 and extends crossing a portion of the sections 223 a, 223 b of the second metal circuit 223.

FIG. 3E is a schematic view of a metal layer formed on the insulating layer to connect the sections 223 a, 223 b of the second metal circuit 223. A metal layer is deposited on a portion of the insulating layer 230, the sections 223 a, 223 b of the second metal circuit 223 to form a connecting section 240 to connect the sections 223 a, 223 b of the second metal circuit 223. The first metal circuit 222 and the second metal circuit 223 on the transparent conductive pattern layer intersect with each other by the connecting section 240. The insulating layer 230 is disposed between the first metal circuit 222 and the second metal circuit 223 to electrically isolate the first metal circuit 222 and the second metal circuit 223.

FIG. 3F is a schematic view of an LED chip disposed on the first metal circuit and the second metal circuit. The first metal circuit 222 and the second metal circuit 223 respectively extend and connect to a positive electrode and a negative electrode, and the LED chip 140 is disposed on the positive electrode and the negative electrode so as to electrically connect to the first metal circuit 222 and the second metal circuit 223.

FIG. 4 is schematic views showing an intersection circuit according to the manufacturing flow charts depicted in FIG. 3A-3F. The intersection circuit 300 includes a transparent substrate 200, a transparent conductive pattern layer 212, a first metal circuit 222 and a second metal circuit 223, an insulating layer 230 and a LED chip 400. The transparent conductive pattern layer 212 is disposed on the transparent substrate 200, and the first metal circuit 222 and the second metal circuit 223 on the transparent conductive pattern layer 212 intersect with each other. The insulating layer 230 is disposed between the second metal circuit 223 and the first metal circuit 222 to electrically isolate the first metal circuit 222 and the second metal circuit 223.

The LED chip 400 is disposed on the first metal circuit 222 and the second metal circuit 223 and electrically connected to the first metal circuit 222 and the second metal circuit 223. The LED chip 400 is disposed on the metal circuits by flip chip, and the method of disposing includes fixing the light emitting chip on the metal circuit through a silver glue of a eutectic bonding. The LED chip 400 is suitable for emitting a light, and a portion of the light emits toward the transparent substrate.

According to an embodiment of the present invention, the substrate comprises a glass substrate, a plastic substrate or a flexible substrate. The thickness of the transparent substrate can be 1.1 micrometers (μm). The transparent conductive layer can be a conductive layer with indium tin oxide. The material of the metal circuit is, for example, gold, aluminum, copper, or alloy thereof. A material of the insulating layer is, for example, silicon oxide, nitride dioxide or a common-used insulating material.

It should be noted that the above-mentioned first metal circuit, the second metal circuit, the insulating layer, the metal circuit pattern or the shape, the position, the size and the amount, the located of the positive electrode and the negative electrode of light emitting chip only serves as an example and is not intended to limit the present invention.

Although the present invention has been disclosed above by the embodiments, they are not intended to limit the present invention. Anybody skilled in the art can make some modifications and alterations without departing from the spirit and scope of the present invention. Therefore, the protecting range of the present invention falls in the appended claims. 

1. A light emitting diode (LED), comprising: a transparent substrate; a first transparent conductive layer disposed on a region of the transparent substrate; a second transparent conductive layer disposed on the other region of the transparent substrate and electrically isolated from the first transparent conductive layer; a plurality of metal circuits respectively disposed on the first transparent conductive layer and the second transparent conductive layer, and cover portions of the first transparent conductive layer and the second transparent conductive layer; and a LED chip disposed on the metal circuits and electrically connected to the metal circuits, wherein the LED chip is suitable for emitting a light and a portion of the light emits toward to the transparent substrate.
 2. The LED as claimed in claim 1, wherein the transparent substrate comprised a glass substrate, a plastic substrate or a flexible substrate.
 3. The LED as claimed in claim 1, wherein a material of the first transparent conductive layer and the second transparent conductive layer comprises indium tin oxide.
 4. The LED as claimed in claim 1, wherein a material of the metal circuits comprises gold, aluminum, copper, or an alloy thereof.
 5. A light emitting diode (LED) device, comprising: a transparent substrate; a transparent conductive pattern layer disposed on the transparent substrate; a first metal circuit and a second metal circuit on the transparent conductive pattern layer intersect with each other, wherein the second metal circuit and the first metal circuit electrically isolated from each other; a insulating layer disposed between the first metal circuit and the second metal circuit to electrically isolate the first metal circuit and the second metal circuit; and a LED chip disposed on the first metal circuit and the second metal circuit and electrically connected to the first metal circuit and the second metal circuit, wherein the LED chip is suitable for emitting a light and a portion of the light emits toward to the transparent substrate.
 6. The LED device as claimed in claim 5, wherein the transparent substrate comprised a glass substrate, a plastic substrate or a flexible substrate.
 7. The LED device as claimed in claim 5, wherein a material of the first transparent conductive layer and the second transparent conductive layer comprises indium tin oxide.
 8. The LED device as claimed in claim 5, wherein a material of the the first metal circuit and the second metal circuit comprises gold, aluminum, copper, or an alloy thereof.
 9. The LED device as claimed in claim 5, wherein a material of the insulating layer comprises silicon oxide or nitride dioxide.
 10. A manufacturing method of a light emitting diode (LED), comprising: providing a transparent substrate; forming a first transparent conductive layer on a region of the transparent substrate; forming a second transparent conductive layer on the other region of the transparent substrate and electrically isolated with the first transparent conductive layer; forming a plurality of metal circuits on the first transparent conductive layer and the second transparent conductive layer respectively, and covering the portions of the first transparent conductive layer and the second transparent conductive layer; and disposing a LED chip on the metal circuits and electrically connected to the metal circuits.
 11. The manufacturing method of the LED as claimed in claim 10, wherein a material of the transparent conductive layer is indium tin oxide.
 12. The manufacturing method of the LED as claimed in claim 10, wherein a method of forming the first transparent conductive layer and the second transparent conductive layer includes a photolithography process.
 13. The manufacturing method of the LED as claimed in claim 10, wherein a method of forming the first transparent conductive layer and the second transparent conductive layer includes an etching process.
 14. The manufacturing method of the LED as claimed in claim 10, wherein a method of disposing the LED chip comprises disposing the LED chip on the metal circuits through a silver glue or an eutectic bonding.
 15. A manufacturing method of a light emitting diode (LED), comprising: providing a transparent substrate; forming a transparent conductive pattern layer on the transparent substrate; forming a first metal circuit and a second circuit on the transparent conductive pattern layer across each other, wherein the second metal circuit and the first metal circuit electrically isolated from each other; disposing a insulating layer between the first metal circuit and the second metal circuit to electrically isolate the first metal circuit and the second metal circuit; and disposing a LED chip on the first metal circuit and the second metal circuit and electrically connected to the first metal circuit and the second metal circuit.
 16. The manufacturing method of the LED as claimed in claim 15, wherein a material of the transparent conductive pattern layer is indium tin oxide.
 17. The manufacturing method of the LED as claimed in claim 15, wherein a method of forming the transparent conductive pattern layer comprises a photolithography process and an etching process.
 18. The manufacturing method of the LED as claimed in claim 15, wherein a material of the first metal circuit and the second metal circuit comprises gold, aluminum, copper, or an alloy thereof.
 19. The LED device as claimed in claim 15, wherein a material of insulating layer comprises silicon oxide or nitride dioxide.
 20. The manufacturing method of the LED as claimed in claim 15, wherein a method of disposing the LED chip comprises disposing the LED chip on the first metal circuit and the second metal circuit through a silver glue or an eutectic bonding. 